Surgical snare



H. NEIVERT SURGICAL SNARE Nov. 24, 1931.

Filed July 18, 1930 INVENTOR Ha rru; Nelverf y I ATTORNEYS Patented Nov. 24, 1931 PATENT orrrcg HARRY NEIVEBT; or new YORK, N. Y.

SURGICAL SNARE 'Application filed' J'uly 18,

This invention relates tosurgical instruments, and more particularly to a surgical snare.

A snare is often used in surgical operations, particularly in'tonsi'l'eetomy. The conventional snare includes relatively movable members, one of which. is arranged to receive the bent or hook-like ends of a snare wire, and suitable additional mechanism for relatively moving the members soas to tighten the snare loop. These instruments are characterized by considerable difiicul'ties and disadvantages which center about the method of anchoring the ends of the snare wire on the movablemember. To begin with it'is difficult to thread or mount"'the snare wire on the instrument. After the wire is mounted and while the-instrument is fully open to expand the-loop the hooked ends of thewirepro'ject from the instrument'and are a source of annoyance and danger," inasmuch as they'maycatch, on the'patients lip during the insertionofthe' instrument in his mouth, or on the back of the patients throat when beginning touse the instrument;

After the loop has been contracted and pulled within the instrument to remove one of the tonsils, diificulty frequently arises in opening the instrument due to the fact that the'hooked ends ofthe'wire tend to catch on the inner wall of the instrument when it is attempted to move" them in the outward direction. 1 When the instrument has been opened it is customary-Eforthe surgeon to exp and' the loop with his fingers in preparation for the removal of'the second tonsil, and during this step the 'doctors fingers may be scratched or cut by the exposed bend or hooked ends of the snare; This is particularly inconvenient because the snare wire is at this time badly contaminated because of its previous contact with the diseased tonsil. After the second tonsil has been re-- moved, difficulty again arises in removing the snare wire from the instrument.

One primary object of my invention is to overcome all of these difliculties and disadvantages, and to provide a surgicalsnare 1930. Serial No. 468,824.

ed for readily receiving the snare wire, and whichwill: be smooth in operation both when contracting as well as when expanding the snare loop.

The mechanism for causing relative movement of the fixed and movable members of the snare in order to tighten the loop ordinarily comprises appropriate finger grips on the fixed and movable members which are pulledtogether during the operation. As ordinarily constructed, difliculty arises when the finger grips are brought nearly together because of the fact that thefleshy art of the palm and fingers of the hand of t 1e surgeon is apt to be caught between the finger grips, and squeezed or pinched when he applies full pressure to complete the operation. It is a'further object ofthe present invention to overcome this difficulty, and to shield the hand of the surgeon against pinching with out meanwhile interfering with the operation or the instrument over the full possible range of movement.

The pressure which may be applied on the instrument tends to decrease when the finger grips are brought close together, inasmuch as r is needed and the grips must be within convenient reach when the instrument is fully expanded. In accordance with a further object of, my invention, the instrument is so designed that the-operation may proceed in a number of different stages, in each of which the hand may be diflerently'positioned on the finger grips so as to permit the application of optimum pressure on the instrument. or

To the accomplishment of the foregoing and such other objects as will hereinafter appear, my invention consists in the surgical snare elements and their relation one tothe other, as hereinafter are more particularly described and sought to be defined in the claims. The specification is accompanied by drawings which show the preferred embodi-- ment of my. invention, and in which:

Fig. 1 is a front elevation of my improved snare, 7

Fig. 2 is aside elevation of the same; Fig. 3 is a detail of the end of the snare; Fig. 4 is a section taken through the end of the snare; and r members 2 and 4 and a snare wire or loop 6.

Additional mechanism of any desired type may bexprovided for causing relative movement of the members 2 and 4. For convenience of reference, I shall refer to the member 2 as a fixed member, and the member 4 as a movable memberwhic'h acts as'a pull rod and may be drawn-within the fixed member 2 in order to contract or tighten the snare loop 6 until the latter isnfinally drawn entirely within the fixed member 2.

The snarewire 6 is not really a part of the instrument per se, inasmuch as a new wire is used foreach operation. A length of wire isbent' in the formof a. loop and the ends are bent to form the hooks 8 and 10. In prior instruments the movable member 4 consisted of a fiat or sometimes a channel-shaped strip of metal which was provided with a plurality of spaced apertures, and the wire was threaded thereon by inserting one of the hooks s through one of the apertures, and thereafter inserting the other of the hooks in the opposite direction through another of the apertures. Inasmuch as the wire is a high grade of steel piano wire or like resilient wire, this operation frequently proved troublesome. In

the present instrument the hooks 8 and 10 may simply be inserted in the single aperture 12 of the movable member 4 which, of course, may be done with rapidityand ease.

{I a The movable member 4 is then pulled with V in the fixed member 2 sufficient distance for the beginning of the loop to reach the fixed member in order to prevent the loop from escaping from the movable member. In prior instrum ents the ends of the hooks 8 and 10 would at'this time frequently project slightly, or even considerably, fro-m the end of the fixed member 2, and this would prove a source of considerable annoyance because the sharp ends of the wirewere apt to catch on the lips V or throat of the patient. Furthermore, after '-i -4 with means for receiving and protectively theloop had been fullycontracted by pulling the same within the fixed member, it was sometimesdifiicult' to again eject and expand ;the loop,'-inas much as the ends of the wire would tend to expand outwardly ag in the inner walls of the fixed member 2 and catch in the same during the outward movement. Then, when the surgeon attempted to spread the sidesof the loop apart preparatory to removing the second tonsil, he was apt to. cut his fingerson the ends ofthe snare. All of these difiicultiesare overcome in the present invention by providing the movable member housing the ends of the snare wire. In the present case this is done by making the movable member 4 hollow, so that when the hooked ends 8 and of the snare are inserted through the aperture 12 the ends are protectively housed within the hollow interior of the movable member. structurally the desired results most simply beobtained by making the movable member or pull rod 4 in the form of a tube, the diameter of which, of course, should be less than the inside diameter of the fixed tube 2 by about twice the diameter of the snare wire.

The tubular pull. rod 4 is preferably provided with a pluralityof apertures such as the apertures 12 and 14 shown inFig. 4, and the hooks 8 and 10 may, both be hooked together in either the aperture 12 or the aperture 14, or, if desired, one hook may be insertedin each of the apertures in the manner illustrated in F ig. 4. In any case, it willbe evident that the springy and relatively sharp ends of the hooks 8 and 10 are housed within the rod 4, and thereforecan never expand outwardly to prevent downward movement of the rod 4 with respect to the rod 2, and'are protectively shielded so that they can not scratch or cut the patient or surgeon at any time during the'entire operation.

The conventional manner in which the mov able pull rod 4 may bedrawn within the fixed tube 2 is by means of relatively movable finger grips of-the general type illustrated in Figs. 1 and ,2 of the drawings. A fixed finger grip is detachably attached by means of a thumb screw 22 to theu'pper end of the fixed member,2., A movable finger grip comprising a pair of finger rings 24 is arranged to surround and to slideon the outside of the fixed member 2. It is attached'to the movable member 4 by means of a cross bridge, not shown, which slides within a slot 26 cut through the upper portion of the fixed memhand is contracted to pull the finger grips together, and so to contract the snare loop. -11 Considerable range of movement is needed in order to have a full opening of the loop when the operation is begun. At the end of the operation the finger grips therefore come quite closely together and, inasmuch as considerable pressure is needed, I have found that the fleshy part of the fingers and palm of the hand is frequently caught'and pinched between the fixed and movable fingergrips. This is particularly true due tothe presence I of the thumb screw 22, which, however, is

essential for facilitating cleaning of the instrument.

To prevent this annoyance I provide the movable finger grip or finger rings 24. with a shield 28 extending backward on either side of the movable finger grip, in the manner shown in the drawings. This shield presents an added surface to the fingers of the surgeon which makes it possible for him to exert greater pressure on the instrument and at the same time protects the hand against pinching, for when the finger grips are brought together the sides of the shield 28 surround the lower end of the fixed finger grip and the thumb screw 22, as is schematically indicated by the dotted line position 28' in Fig. 2.

When the fixed and movable finger grips are brought nearly together the hand of the surgeon is so nearly completely closed that it is difiicult to obtain the desired pressure. Accordingly, the operation may be begun with the thumb in ring 20 and the index and middle fingers in rin s 24, as was before explained. When, however, the operation has partially proceeded, the strength of grip may again be increased by anchoring the thumb in back of ring 20 and against the ressure surface 30 on top of the fixed grip. inally, when the finger grips have been brought almost together, the strength of the grip may again be increased to permit the application of extra pressure by removing the fingers from rings 24 andapplying the same to the pressure surfaces 32, which I provide on the lower face or side of the rings 24 opposite the fixed grip 20. The position of the hand at this time is illustrated in Fig. 5, in which it will be observed that the thumb and palm of the hand is anchored in back of the fixed finger grip 30, while the fingers of the hand are applied against the movable pressure surface 32. It will also be evident that the fleshy part of the hand is protected against pinching by the protective shield 28.

The mode of constructing and using and the many advantages of my improved surgical snare will, it is thought, be apparent from the foregoing detailed description thereof. The snare wire may readily be applied to and removed from the instrument, and the hooked ends thereof are protectively housed to prevent injury during the operation and to insure that the sliding movement of the instrument will be smooth in the outward as well as in the inward direction. The hand of the surgeon is protected against pinching during the operation and the, application of extra pressure is facilitated by the provision of broad pressure surfaces, different ones of I which may be successively employed at different stages of the operation sothat optimum pressure may always be obtained.

It will be apparent that while I have shown and described my invention in the preferred form, many changes and modifications may be made in the structure disclosed without departing from the spirit of the invention defined in the following claims.

I claim: I Y 1.. A surgical snare comprising a fixed memher, a member movable relative to the fixed member for pulling the hooked ends of a.

snare wire into the fixed member in order to tighten the'snare'loop, and means for causing relative movement of the movable and fixedof a snare wire into the fixed member inorder to tighten the snare loop, andv means for causing relative movement of the movable and fixed members, said movable member being tubular and provided with one or. more apertures in the tubular wall thereof for receiving the ends hooked of thesnare wire, whereby the said hooked ends are carried within and lar :member.

3. A surgical snare comprising a fixed tub-- ular member, a member movable relative to the fixed member for pulling the hooked ends of a snare wire within the fixed tubular memher in order to tighten the snare loop, and means for causing movement of the movable member within the fixed member, said movable member being tubular and provided with one or more apertures in the tubular wall thereof for so receiving the hooked ends of the snare wire that they are protectively housed within the tubular movable member.

4. A surgical snare comprising a fixed finger grip, a movable finger grip, and a shield for protecting the hand of the user when the fixed and movable finger grips are being operated.

5. A surgical snare comprising a fixed member, a finger grip thereon, a movable member for tightening the snare loop, a fin ger grip attached thereto, and a shield on the movable finger grip for protecting the hand of the user when the fixed and movable finger grips are brought close together.

' 6. A surgical snare comprising a fixed member, a finger grip thereon, a movable member, a finger grip attached thereto, said movable member being provided with one or more apertures for receiving and protectively housing the ends of a wire snare, and one of said finger "rips being provided with a shield for shielding the hand of the user when the fixed and movable finger grips are operated.

7. A surgical snare comprising a fixed tubular member, a finger grip thereon, a movprotectively housed by the tubus its abletubular member adapted to slide within the fixed'tubular member, a, finger grip attached thereto, said movable tube being provided with one or more apertures in the wall thereof for receiving and protectively housing the ends of awire snare, said movable finger grip bein provided with a pair of finger for'shielding the hand of the user when the fixed and movable grips are brought nearly together.

'8'. A surgical snare comprising a fixed tubular member, a finger grip attached thereto, a movable tubular member adapted to slide within the fixed tubular member, a finger grip attached thereto for causing movement of the movable member within the fixed member, said movable member being provided with one or more apertures in the tubular wall thereof for receiving and protectively housing the ends of a Wire snare, said'movable finger grip being provided with a pair of finger rings, a shield adjacent said finger rings for shielding the hand of the user when the fixed and movable grips are: brought nearly together, and a flat outer surface on the sides of the rings opposite the fixed finger grip for permitting the application of extra pressure when the fixed and movable grips are brought nearly together.

Signed at New York city, in the county of New York and State of New York this 12th day of July, A. D. 1930.

HARRY NEIVERT.

rlngs, and 'a s ield adjacent said finger rings 

